Is the incidence of registrable age-related macular degeneration increasing?

Age-related macular degeneration (ARMD) is a growing public health problem in Britain; currently its aetiology is unclear. The aim of this study was to test the hypothesis that the age specific incidence of blinding ARMD has increased in Britain in the past 50 years, using data on cause of visual loss in people registered as blind, published every 10 years since 1950.

Data were abstracted from published sources for the years 1950, 1960, 1970, and 1980. Data for the standard year, 1990, were provided in a database from the Office of Population Censuses and Surveys. The numbers of new registrations attributed to ARMD per head of population were compared with registrations for cataract, glaucoma, and optic atrophy. Indirect standardisation was used to control for changes in the age structure of the population over time.

After controlling for changes in the age structure of the population, registration rates for all causes, cataract, glaucoma, and optic atrophy have decreased while registrations attributed to ARMD have increased in the order of 30-40%.

These findings are compatible with the hypothesis that the incidence of ARMD is increasing in Britain. It is difficult to exclude potential sources of bias in these data, however, particularly with respect to classification and coding of cause; more reliable population based data on ARMD in Britain are needed.